Pipe-threader.



E. S. STACK.

PIPE THREADER.

APPLICATION FILED MAR. 10, 1911.

Patented July 20, 1915.

Witnesses 3 Z m pm. me m Z E %M46M I COLUMBIA PLANOGRAPH 1:0,, WASHINGTON.

ent sizes they are made relatively adjust- ELMER s. STACK, or soMEBvILLn.'lvrassacnusnrrs.

PIPE-THREADER.

Specification of Letters Patent.

Patented J lily 20, 1915.

Application filed March 10, 1911. Serial No. 613,612.

To all whom it may concern: 1

Be it known that I, ELMER S. STACK, a citizen of the United States, and a resident of Somerville, in the county ofMiddlesex and State of Massachusetts, have invented an Improvement in Pipe-Threaders, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts. i

This invention relates. to thread cutters and other tools and among other objects pro vides simple and efi'ective means'for guiding the cutter in cutting threads on long or short pipes.v

The character of the invention may be best understood by reference to the follow-- ing description of an illustrative embodiment thereof shown in the accompanying drawing, wherein:

Figure 1 is a side elevation of an illustrative pipe threader embodying the invention; Fig. 2 is a view lookingtoward the left of Fig. 1; Fig. 3 is a view looking toward the right of Fig. 1; Fig. l is a plan view of Fig. 1; Fig. 5is a detail view of a,

die and die stock; Fig. 6 shows a device which may be used in connection with the die stock shown in Fig. 5; and Fig. 7 is a section taken on line 77 of'Fig. 6.

The illustrative pipe threader to be described embodying the invention may be used in connection with any suitable pipe holding means, such for example as a vise (Figs. 1 to 4) comprising a body or frame 1 conveniently of sheet material bent into U- shape form, the ends of the legs of the U being riveter or otherwise secured to a U-shaped base plate 3 also of sheet material. On said body are mounted jaws 5 of steel or other suitable material which may be formed to present gripping faces. Herein said jaws are grooved longitudinally pre-' senting sharp corners as shown in Fig. 3. adapted to nip a pipe or other device held therebetween and prevent rotation thereof in the jaws as on the cutting of threads on such pipe or device.

To permit the jaws to grip pipes of diiferable, the lower jaw 5 being shown bolted or otherwise secured on the top of the base plate 3 and in a lateral recess in the body 1. The upper jaw in the present embodiment of the invention is adjusted relatively to the lower jaw and is adapted to slide along the i 4 vertical edges of the recess in the U-shaped sheet body 1. To this end the upper jaw is connected to a screw 7' threadedinto a block 9 fitted in the closed end of the U-shape body and suitably secured thereto The screw 7 may be rotatively connected'to the latter being guided along edges of" the U- plate. The screw 7 is able handle 15.

A visesuch as described is extremely light, small, compact, and cheap in construction provided with a suitpermitting it to be readily carried from place to place and set up.

Having described a preferred construetion of vise I will now describe means adapted'to be used in connection therewith for threading purposes. To this end there is provideda die stock .17 preferably square in shape to'conform to and receive a usual die 19 (Fig. 5 Various sizes of'di'es will be used according to the size of pipe to be threaded. To permit different dies to be readily inserted and removed in said die stookf fastening. screws 21 are provided threaded into ribs 23 on opposite sides of said die stock. Portions of the heads of the screws are removed so that they may be turned to permitthe ready removal of the die. 25 bored to receive the stem of a handle .27 adjustably held in said boss by a suitable set screw 29. 'l-leretofore in threading short pipes considerable diffioulty has been experienced in effecting a proper centering of the die owing to the short length of the pipe operated on. Also, die stocks as usually constructed have an elongatedboss or sleeve extending in advance of the die toprovide' for the proper guiding of thejlatter; The presence of this elongated sleeve makes it impossible to thread short lengths of pipes.

One of the objects of the invention is to eliminate the necessity of such a sleeve and thereby permit the die to work up close to the ends of the jaws in which the pipe is The die stock is provided with a boss v held. To this end a guide member or mandrel 31 is provided (Fig. 7) for co'ojperation with the die stock and a suitable fixed guide. Herein one end of said mandrel is extended within the die stock and threaded or other.-

wise secured thereto. The mandrel projects from said boss throughthe die and beyond the face thereof a substantial distance. Any suitable bearing or guiding arrangement may be provided for the outer free end of this mandrel. Herein there is provided a bracket 33 having one end apertured to r0- tatively receive a free end of said mandrel, the opposite end of said bracket having an elongated slot receiving a hand screw 35 threaded to the body of the vise, as shown in Fig. 3. By this construction the bracket may be adjusted relatively to the jaws of the vise to permit the proper centering of the mandrel and also to and from operative position. While as shown herein the mandrel is secured to the die stock and slides in said bracket, it will be understood that the mandrel might be fast on said bracket and loose in said die stock.

In use a short length of pipe, such as P, is clamped between the jaws 5 with the portion thereof desired to be threaded projecting beyond the ends of said jaws. Then the die stock is presented to said pipe and the mandrel 31 is thrust through the pipe P and the hole in the bearing bracket 33 until the face of the die engages the end of the pipe. The handle 27 is then rotated to cut the thread on the pipe. By this construction the die will be free to feed along the pipe and cut threads therein close to the ends of the jaws holding the pipe without interference. The die is positively guided by the mandrel and bracket described at a point remote from the die, thereby maintaining the accurate centering of the die and enabling threads to be accurately cut on the pipe. The pipe in no way is utilized to effect the guiding of the die thereon other than at the point of application of the die to the pipe. Thus, the weight of the die stock does not come upon the pipe in a manner tending to strain, mutilate or distort the pipe, as heretofore, where it has been attempted to guide the die stock by devices clamped to and within the pipe.

After the pipe has been threaded the die stock and its mandrel together are withdrawn from the pipe, and the jaws of the vise are separated permitting the removal of the pipe. No other operation is necessary. There are no devices within the pipe to be unclamped and removed.

Where extremely short pipes are being threaded a ring 37 conveniently of a section of pipe corresponding to that to be threaded may be inserted between the jaws of the vise at their ends opposite to that occupied by the pipe to be threaded to keep the jaws of the vise evenly spaced.

In order that the die stock may be readily adapted for threading long pipes as well as short pipes, the mandrel 31 may be removed nd a supplemental guide may be provided. Hereinthis guide comprises a boss 39 having feet 41 which may be held to the die stock by the same screws 21 which hold the die in place in said die stock. The boss 39 may be provided with removal bushings 43 to conform to the exterior diameter of the pipe to be threaded. When the die stock is used in threading pipes which are sufficiently long to make it unnecessary to use the mandrel and guide bracket, the guide 39 is sufficient to keep the die properly centered.

WVhile the invention is described in connection with a thread cutter it will be understood that it is applicable to other tools.

It is not indispensable that all of the features of the invention be used conjointly since they may be used separately to ad vantage.

Having described one embodiment of the invention without limiting the same thereto, What I claim as new and desire to secure by Letters Patent is:

1. A threading device comprising in combination, means for holding an article to be threaded; a die stock; and guiding means for the latter projecting from said die stock to receive support from said holding means.

2. A threading device comprising, in combination, means for holding an article to be threaded; a die stock; a die therefor; supporting means, and guide means projecting from said die stock to said supporting means for positioning said die stock.

3. A threading device comprising, in combination, means for holding a pipe to be threaded; a die stock and its die; supporting means, and a mandrel extending from said die stock through said pipe to said sup porting means for positioning said die stock.

4. A threading device comprising, in combination, means for holding an article to be threaded; a die stock having a guide mandrel secured thereto; and guiding means on said holding means for said mandrel.

5. A device of the class described comprising in combination a die stock; a die therefor; supporting means; and guide means independent of the article operated on extending from said die stock to said supporting means for positioning said stock.

6. A device of the class described comprising in combination, a die stock; a die therefor; a support; and a guide member for insertion through a short pipe independently thereof and connecting said stock and support to guide said stock and die while acting on said pipe.

7. A threading device comprising, in combination, a vise having jaws for holding an article to be threaded; a bearing bracket adjustably mounted on said vise adjacent said bearing bracket.

8. A device of the class described comprisjaws; a die stock; a die carried thereby for active engagement With one end of an article to be threaded; and guiding means projecting from said die stock beyond the opposite end of said article for guidance by said ing in combination, a die stock; a die therefor; a mandrel projecting from said stock for insertion through a short pipe independ- Copies of this patent may be obtained for five cents each, by addressing the Comm ently thereof; and means for supporting ELMER S. STACK.

Witnesses:

HENRY T. WILLIAMS, ROBERT H. KAMMLER.

Washington, D. G.

issioner of Patents, 

